Weird, wild and wacky holidays to celebrate in December 2016 (photos)

CLEVELAND, Ohio -- Solve a crossword puzzle, binge-watch "Planet of the Apes," learn to play the cello and have a Festivus Airing of the Grievances. All this fun is allowed because you're celebrating the weird and wacky unofficial holidays in December.

The last month of the year is filled with important holidays. December's major religious and cultural holidays are Hanukkah (Saturday, Dec. 24-Sunday, Jan. 1), Christmas (Sunday, Dec. 25) and Kwanzaa (Monday, Dec. 26-Sunday, Jan. 1).

The shortest day of the year, known as winter solstice, falls on Wednesday, Dec. 21.

Somber remembrances in December include World AIDS Day (Thursday, Dec. 1), International Day of Persons with Disabilities (Saturday, Dec. 3), National Pearl Harbor Remembrance Day (Wednesday, Dec. 7) and Human Rights Day (Saturday, Dec. 10).

Soil is more than just the stuff we walk on. It's also "a critical component of the natural system," according to the World Soil Day website, which also informs us that there are 60,000 soil scientists around the world. World Soil Day is held on Dec. 5 because that date was the official birthday of Bhumibol Adulyadej, the former King of Thailand, who officially sanctioned World Soil Day.

This holiday celebrating monkeys, apes, tarsiers and lemurs, was started by art students at Michigan State University in 2000, and promoted online. Celebrate Monkey Day with a marathon of the "Planet of the Apes" movies, starting with the original movie, 1968's "Planet of the Apes" starring Charleston Heston. Then watch the reboot series that started with 2011's "Rise of the Planet of the Apes" with Andy Serkis portraying the intelligent ape Caesar.

This day honors not only the world's mountains - which cover 22 percent of the earth's land surface -- but also the 915 million mountain people around the world. In Northeast Ohio, we have some pretty steep hills and tall staircases, including the new 90-feet-tall Fort Hill Steps at the Rocky River Reservation in the Cleveland Metroparks. Climb one of these while warbling "Climb Every Mountain," and you'll have done your part for International Mountain Day.

Poinsettias, the best-selling potted plant in the United States and Canada, deserve a day of their own. The date marks the death of Joel Roberts Poinsett, an American botanist. In the 1800's, Poinsett sent cuttings of the plant growing in Southern Mexico - where it's a perennial shrub 10-15 feet tall -- to the United States, according to the website poinsettiaday.com. There are more than 100 varieties of poinsettias, and the plant comes comes red, white, pink, burgundy, marbled and speckled.

In-flight movies. Stewardesses. Printable boarding passes. Think how far air travel has come since Dec. 17, 1903, when Orville and Wilbur Wright made their first successful flights in a heavier than air, mechanically propelled airplane near Kitty Hawk, North Carolina. The brothers grew up in Dayton, Ohio, and began experimenting with airplanes there. On Wright Brothers Day, take a day trip to Dayton to visit many of the locations associated with the aviation pioneers.

Crossword Puzzle Day, Wednesday, Dec. 21

If you have ever solved a Sunday New York Times crossword puzzle, this is the day for you. December 21, 1913, was the date when the first published crossword puzzle appeared in the newspaper New York World. Created by Arthur Wynne, that early puzzle was shaped like a diamond and had no internal black squares. Within a decade, crossword puzzles were featured in numerous American newspapers, according to the website Crossword Tournament.com. So sharpen your pencil and tackle a crossword puzzle to celebrate Crossword Puzzle Day. Bonus points if you can do it in pen.

Don't claim that you've never taken a gift you didn't want and recycled it by giving to someone else. Regifting is a sin only if you forget to remove the gift tag; it proves that the Walking Dead Chia Pet you're foisting on an office mate was originally meant for you. The etiquette of regifting was discussed in an episode of "Seinfeld," so watch it while re-wrapping recycled gifts on National Regifting Day.

Sick of all of the commercialization that goes with Christmas? Do you yearn for a simple, yet meaningful celebration with no trees, stockings or ugly sweaters? Then you need Festivus, the holiday for the rest of us. Since it was featured on a 1997 episode on "Seinfeld," families have been observing Festivus by putting up a Festivus pole, having the Airing of the Grievances and Feats of Strength. Find out more at this site devoted to Festivus. It even has the entire "Seinfeld" script. Make your own Festivus miracle!

Make Cut Out Snowflakes Day, Tuesday, Dec. 27

The best holiday decorations are the ones that are handmade, and cut-out snowflakes are a perfect example. It's been years since some of us have folded and cut paper to make lacy snowflakes, but why not learn how again? Here's a tutorial, so grab scissors and paper, and make an indoors snowstorm.

Fruitcake doesn't deserve its bad reputation. I've enjoyed moist, delicious fruitcake, but most people think of it as a brick-hard, dried-out cake filled with brightly colored bits of unrecognizable food. Fruitcake Day comes after Christmas, because by Dec. 27, you need to either finish off the fruitcake or toss it in the garbage. When confronted with hard, dry fruitcake, simply dunk it into a mug of hot chocolate. Yum!

The cello is a bass instrument in the violin family, held upright on the floor between the legs of the seated player. International Cello Day falls on the birthday of the famous cellist Pablo Casals, who performed for Queen Victoria and President John F. Kennedy. If Cello Day inspires you to take up the instrument, that's fantastic. But non-musicians can participate by listening to Bach's Suites for Unaccompanied Cello. Classic FM has a guide to these works, with sound clips from six great cellists.